Question

using prototype method we can create new methods… like…

Object.prototype.newMethod=function(){
   // do something
}

Here I am defining the newMethod with an anonymous function… now if I want to use this method, I have to use it like: <object>.newMethod();

But now I want to create a new method which I can use like: <object>.newMethod;… no brackets… How can I do that…??

please don’t use any jQuery…

Answer 1

I can’t really understand why you would want to do that, but it is possible, albeit with a nasty hacky workaround. What you’re actually looking for, AFAIK, is a magic property (like the someArray.length property).

var foo = {val:'foo'};
foo.length = (function(that)
{
    return function()
    {
        return that.val.length;
    }
})(foo);
//at this point foo.length(); returns 3, but still requires parentheses
//so, build another closure, and assign a valueOf method to the lenth method:
foo.length.valueOf = (function(method)
{
    return function()
    {
        return method();//call the length method
    }
})(foo.length);
console.log(foo.length +1);//logs 4
foo.val += 'bar';
console.log(foo.length);//logs 6
//BUT:: be carefull!!
alert(foo.length);//coerces to string, we haven't redefined the toString method, so the function code will be alerted
alert(foo.length + '');//alerts 6

This is just to show you that, yes it is theoretically possible, but please, please, don’t use this kind of overly polluted hacks… I haven’t thoroughly tested this, but ATM, I’ve already noticed that console.log(foo.length); can return a different value, not sure why, yet:

foo = {val:'foo'};
foo.length = (function(that){return function(){ return that.val.length;};})(foo);
foo.length.valueOf = (function(method){return function(){return method();};})(foo.length);
foo.length;//returns 3, great
foo.val += 'bar';
console.log(foo.length);//logged 3 at first, now it's back to logging 6!<-- don't trust this is the conclusion